What is the difference between brown dwarfs and Jupiter?

Answer 1

Brown dwarves generate more energy (as IR emission) than they reflect. Jupiter reflects more energy than it generates.

Answer 2

Mass.
Brown dwarf stars are between 12 and 75 times the mass of Jupiter.

Answer 3

Brown dwarfs are essentially "failed stars", created out of interstellar gas just like other stars, but never reaching the critical mass of about .08 solar mass (80X mass of Jupiter) needed to ignite hydrogen fusion it its core. In this state, they are considered to be "Jupiter-like", with scientists drawinig the dividing line at about 12X mass of Jupiter but not above 80X. A major difference is the fact that although they do not reach that point of hydrogen fusion, in the beginning there is a brief phase of deuterium fusion. Once the deuterium is consumed, the phase is over. Jupiter never reached a mass or temperature anywhere close enough for any kind of fusion to occur. Otherwise, the two objects are very similar.

Answer 4

Jupiter doesn't give off any energy because there's no fusion in its core